1. Field of the Invention
The present invention relates generally to a system for continuously positioning a heliostat, and specifically to an automatic hydraulic logic for driving a heliostat.
2. Prior Art
Efforts to concentrate the energy from the sun to produce heat or power date back perhaps to the day of Archimedes. Heliostats are a result of these efforts. They are normally large reflective surfaces which must be continuously positioned to be aimed at the sun and in most cases must be in a normal relationship to the sun at all operative times. Today, there are several methods for harnessing this energy source. For power generation however, high temperature of the medium is necessary, especially for economic reasons. This high temperature can, at the present state of the art, be only gained by concentrating the sun's rays on to a heat exchanger which carries the energy medium. Concentration means that the equipment must be normal to the sun's rays at all times. This normalization is frequently accomplished by employing various positioning devices which are connected to the heliostat. Some prior art devices employ electric/electronic systems to control the motion of the heliostat. Computers are often used for heliostat control positioning. It should be noted that in these cases electrical power must be available to continuously position the heliostat.
The use of heliostats, on any wide scale, as a viable energy service has been limited for several reasons: (1) Availability and low cost of fossile fuel; and (2) Energy storage problems.
Today, however, a real urgency exists for implementation of alternate power sources such as solar power, due to the impending crisis, the high cost of fossile fuel and improvements in energy conversion devices.
Heliostats must be continuously directed or aimed at the sun in order to function at maximum efficiency. Therefore, heliostats require a guidance system to track the sun and a mechanical system to continuously move it in both the horizontal and vertical plane. The prior art devices for continuously moving the heliostat have been energy inefficient, mechanically complex, and required much maintenance.
The present invention provides a device for continuously and simultaneously positioning a heliostat in relation to the sun. The device system uses hydraulic energy coupled with simple hydraulic circuits that provide automatic operation for any kind or form of heliostat to obtain simultaneous movements in the vertical and horizontal axis. No seasonal adjustments are necessary as the hydraulic circuits have inherent capabilities that take care of these variations. No electrical energy in any form is employed in control.